This code details the design and construction of steel railway bridges using the Working Stress Method. It specifies requirements for materials, loads (including standard train, wind, seismic loads), permissible stresses, design of structural components, connections (riveting, bolting, welding), fabrication, and erection.
Lays down guidelines for the design and construction of steel railway bridges.
Quick Reference Values
Modulus of Elasticity of Steel2.0 x 10^5 N/mm²
Unit Mass of Steel7850 kg/m³
Coefficient of Thermal Expansion for Steel12 x 10^-6 per °C
Permissible Axial Tensile Stress (Standard Steel)150 N/mm²
Permissible Bending Stress (Standard Steel)165 N/mm²
Poisson's Ratio for Steel0.30
Key Formulas
f = P/A ≤ σ (Basic stress check for tension/compression members)
f_b = M/Z ≤ σ_b (Basic stress check for bending members)
Practical Notes
This code uses the outdated Working Stress Method (WSM); modern designs use the Limit State Method (LSM).
For any current railway projects, this code is superseded by the specific codes issued by Indian Railways (RDSO), such as the IRS Steel Bridge Code.
The provisions for fatigue (Clause 6.9) are critical and should be carefully evaluated for any assessment of older bridges designed to this code.